<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Struct template root_typeof_helper</title>
<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
<link rel="home" href="../../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset">
<link rel="up" href="../../boost_units/Reference.html#header.boost.units.operators_hpp" title="Header &lt;boost/units/operators.hpp&gt;">
<link rel="prev" href="power_typeof_helper.html" title="Struct template power_typeof_helper">
<link rel="next" href="subtract_typeof_helper.html" title="Struct template subtract_typeof_helper">
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table cellpadding="2" width="100%"><tr>
<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../boost.png"></td>
<td align="center"><a href="../../../../index.html">Home</a></td>
<td align="center"><a href="../../../../libs/libraries.htm">Libraries</a></td>
<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td>
<td align="center"><a href="../../../../more/index.htm">More</a></td>
</tr></table>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="power_typeof_helper.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../boost_units/Reference.html#header.boost.units.operators_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="subtract_typeof_helper.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a>
</div>
<div class="refentry">
<a name="boost.units.root_typeof_helper"></a><div class="titlepage"></div>
<div class="refnamediv">
<h2><span class="refentrytitle">Struct template root_typeof_helper</span></h2>
<p>boost::units::root_typeof_helper</p>
</div>
<h2 class="refsynopsisdiv-title">Synopsis</h2>
<div class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="../../boost_units/Reference.html#header.boost.units.operators_hpp" title="Header &lt;boost/units/operators.hpp&gt;">boost/units/operators.hpp</a>&gt;

</span><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> Radicand<span class="special">,</span> <span class="keyword">typename</span> Index<span class="special">&gt;</span> 
<span class="keyword">struct</span> <a class="link" href="root_typeof_helper.html" title="Struct template root_typeof_helper">root_typeof_helper</a> <span class="special">{</span>
  <span class="comment">// types</span>
  <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <a name="boost.units.root_typeof_helper.type"></a><span class="identifier">type</span><span class="special">;</span>  <span class="comment">// specifies the result type </span>

  <span class="comment">// <a class="link" href="root_typeof_helper.html#id-1_3_43_10_2_34_3_1_5_4-bb">public static functions</a></span>
  <span class="keyword">static</span> <span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">type</span> <a class="link" href="root_typeof_helper.html#id-1_3_43_10_2_34_3_1_5_4_1-bb"><span class="identifier">value</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">Radicand</span> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
<span class="special">}</span><span class="special">;</span></pre></div>
<div class="refsect1">
<a name="id-1.3.43.10.2.34.9.4"></a><h2>Description</h2>
<p>A helper used by <code class="computeroutput">root</code> to take a root of a runtime object using a compile time known index. This template is intended to be specialized. All specializations must conform to the interface shown here. <code class="computeroutput">Index</code> will be either the type passed to <code class="computeroutput">pow</code> or <code class="computeroutput">static_rational&lt;N&gt;</code> for and integer argument, N. </p>
<div class="refsect2">
<a name="id-1.3.43.10.2.34.9.4.3"></a><h3>
<a name="id-1_3_43_10_2_34_3_1_5_4-bb"></a><code class="computeroutput">root_typeof_helper</code> public static functions</h3>
<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
<pre class="literallayout"><span class="keyword">static</span> <span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">type</span> <a name="id-1_3_43_10_2_34_3_1_5_4_1-bb"></a><span class="identifier">value</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">Radicand</span> <span class="special">&amp;</span> base<span class="special">)</span><span class="special">;</span></pre>Carries out the runtime calculation. </li></ol></div>
</div>
</div>
</div>
<div class="copyright-footer">Copyright © 2003-2008 Matthias Christian Schabel<br>Copyright © 2007-2010 Steven
      Watanabe<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
</div>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="power_typeof_helper.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../boost_units/Reference.html#header.boost.units.operators_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="subtract_typeof_helper.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a>
</div>
</body>
</html>
